Each year in the United States, 70,000 hospitalized children are estimated to experience an injury caused by medical management rather than the underlying disease or condition of the patient, defined as an ?adverse event.? Approximately 60% of these adverse events are considered potentially preventable. Little has been done to examine adverse events specifically during the transition when children are discharged from the hospital to home ? postdischarge adverse events. Postdischarge adverse events are important because while they result from care provided during a hospitalization, the majority are not detected until after patients have been discharged to home. Furthermore, the adverse events that are detected in the hospital and appropriately managed still lead to significant symptoms after the patients are sent home. As a result, the postdischarge incidence rates (19% - 28%) in three adult studies were about five to seven times higher than the inhospital adverse event incidence rates. Thus, it is plausible that the postdischarge adverse event incidence rate in children may be much higher than the inhospital rate, as with adults. Thus, efforts in children are needed to investigate postdischarge adverse events to estimate the burden and to identify the risk factors. This prospective cohort study will examine the frequency of adverse events, preventable adverse events, and ameliorable adverse events (aim 1) and identify the types of adverse events (aim 2) in neonatal intensive care unit (NICU) neonates discharged home from the hospital. In addition, the study will examine patient, system, and patient care factors associated with the occurrence of postdischarge adverse events (aim 3). Patients will be identified from the NICUs of Children's Hospital of Michigan and Hutzel Women's Hospital of the Detroit Medical Center. Nurses will recruit NICU neonates prior to discharge, contact their guardians within 4-weeks after discharge to conduct a follow-up telephone interview, and review health records for NICU neonates related to patient care received postdischarge. The nurses will combine the information obtained from the telephone interview and the outpatient health record to screen neonates for adverse events using the following criteria: 1) new or exacerbated symptoms; 2) unplanned health services utilization; and 3) abnormal laboratory test results. If nurses identify any of the above information from the interview responses or health record, they will refer to two physicians who will independently review that neonate's entire health record (inpatient/outpatient) and responses from the telephone interview to determine the occurrence of adverse events. This project addresses a neglected area of patient safety that is related to NICHD's overall mission to improve patient safety during neonatal care. Results from this study will help children's and community hospitals develop systemic interventions to improve the hospital discharge process and pediatric patient safety during the post-discharge period.